Cassie Sainsbury Claims She Was Forced To Smuggle Cocaine

Her plea deal could be torn up.

Accused drug smuggler Cassie Sainsbury's potential six year plea deal with Colombian prosecutors could be torn up after a sensational court appearance.

The 22-year-old told a magistrate on Thursday morning (AEST) that she had been forced to carry 5.8kg of cocaine in 18 headphone packages while travelling from Bogota International Airport in April.

Speaking through a translator, Judge Leon questioned the Adelaide woman on her comments:

"The question is were you under threat to take the drugs with you?" asked the translator.

"...Sí [Yes]."

"Who threatened you?"

"I don't know the exact person," Sainsbury replied.

"How did this threat happen?"

"Because I didn't want to take any package anywhere."

"What would have happened if you didn't take that with you?"

"I was told that my family and partner would be killed."

The revelation came to light during the hearing in which a magistrate was expected to make a ruling on whether to approve the six year gaol sentence her lawyers had negotiated with prosecutors.

It also creates another problem for Sainsbury: the deal was bartered on the basis that she provide the identities of people involved in the drug ring, however she told the court she did not know who had threatened her.

This raises questions about whether she will be able to provide Colombian police with adequate information on the alleged criminals, diminishing the incentive for the prosecutor to slash her sentence.

If the deal is torn up she risks at least 20 years behind bars, which Immigration Minister Peter Dutton says should serve as a warning for Australians heading overseas.

"People need to abide by the laws of that country. If not, they will face serious consequences," he told Seven on Thursday, also noting that the government provided consular but not financial assistance to Sainsbury.

The ruling was suspended to give the judge more time to decide whether the plea deal is "legally valid".